#include <stdio.h>

int main()
{
    int i,j,n = 0,x;
    for(i = 23;n == 0;i += 2)
    {
        for(j = 1,x = i;j <= 4 && x >= 11;j++)
        if(((x + 1) % (j + 1)) == 0)
        x -= (x + 1) / (j + 1);
        else
        {
            x = 0;
            break;
        }
        if(j == 5 && x == 11)
        {
            printf("There are %d fishea at first. \n",i);
            n = 1;
        }
    }
}